Yeah, it's a weird metaphor, especially since plywood is a premium, structural material. I wish my Ikea furniture used plywood. Instead, you get fiberboard.

It's also a good example of how the metaphor this blog post is predicated on can fall apart. Your customers care about durability, but they make purchasing decisions based on cost and outward appearance. In a world like that, where you can't satisfy all requirements at once, you inevitably end up cutting corners on the things the customer cares about but can't measure. But is that right? That's how you end up with $200 furniture that lasts a year or two in a home with children or pets.

It's also easy to neglect cumulative costs. Back to software: does it matter if your app uses 100 MB of memory when it could be using 1 MB? On an individual basis, no, because RAM is cheap. Cumulatively, when every other app developer thinks the same, and when you multiply it by billions of devices, your decision might have actually cost lives if you consider the increased emissions and countless other distant externalities.

A milder version of the blog's claim is definitely true. You should pick your battles. But it's all about trade-offs, there are few problems that truly don't matter to anyone.

The point isn't about utility, it's about aesthetics - it's about how the product is finished. What you use in the back should be the same as elsewhere.

Even furniture from The Old Masters doesn’t have beautiful veneered back panels, but plain, unfinished boards.

Sure, but I'm just explaining Steve's reasoning here. People are saying it's a bad analogy without understanding what he's actually saying.

On the back of the Mona Lisa should be ... another Mona Lisa?

A plywood back would be prone to water damage, however

The best option is plywood for the dimensional stability, varnish for waterproofing, and solid wood edge trim to give some resilience against mechanical damage that would otherwise risk delamination. This also hides the ugly part of the plywood.